Bar twister guide

ABSTRACT

A bar twister guide for use between mill stands, in which a pair of guide rollers are journally mounted on shafts movable axially in a frame. Each roller has an outwardly sloping circumferential shoulder and the two shoulders are in opposed spaced relationship whereby on moving the shafts in opposite directions the gap between the shoulders is adjusted.

United States Patent [191 Groh et al. Dec. 4, 1973 BAR TWISTER GUIDE [75] Inventors: Louis Groh, Bay Ridges, Ontario; Exam'fwraMllton Mehr Harry Joseph Jones Bowmanvme Attorney-Lewis E. l-lanley et :3]. Ontario, both of Canada [73] Assignee: Ferroco Engineering Limited,

Whtb O ta V l y n no Canada ABSTRACT [22] Filed: May 25, 1972 [21] Appl. No.: 256,747 A bar twister guide for use between mill'stands, in which a pair of guide rollers are joumally mounted on hafts movabl axiall in a frame. Each roller has an 52 s y E U S C] i g gg outwardly sloping circumferential shoulder and the Field of Search 250 227 two shoulders are in opposed spaced relationship whereby on moving the shafts in opposite directions 1 the gap between the shoulders is adjusted.

[56] References Cited UNITED STATES PATENTS 3 Claims, 4 Drawing Figures 2,016,141 10/1935 Greer 72/231 PATENTED 4,975 3.776013 sum 1 urs BAR TWISTER GUIDE The present invention relates to a bar twister guide for use in a rolling mill.

When passing bars between sets of mill stands it is necessary to re-orient the bar about its longitudinal axis, usually by a 90 twist. This may be accomplished by providing a bar twister located between the sets of mill stands in the path of the bar. Usually a friction guide is used as a bar twister but an alternate type of bar twister presently in use consists of a pair of rollers each mounted on, a trunnion with the trunnions being linked to be rotated together to change the twist angle. However, the contact elements in these types of bar twisters wear rapidly and the line must be shut down periodically to replace them, in order to prevent malfunctioning. 7

It is an object of the present invention to provide a bar twister, for a rolling mill, in which the twist rollers are adjustable to compensate for wear while the twister is in operation.

An example embodiment of the invention is shown in the accompanying drawings, in which:

FIG. 1 is a persepctive view of a bar between two sets of mill rolls;

FIG. 2 is a side elevational view in cross-section of the bar twister of FIG. 1;

FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2; and

FIG. 4 is a cross-sectional view taken along line 4--4 of FIG. 2.

The example embodiment of the drawings consists of twister located a twister guide having a box frame 11 carrying an upper guide roller 12 and a lower guide roller 14 each journally mounted on a separate shaft 16 which is horizontally disposed and movably mounted axially in opposed walls 18 and 20 of the frame, as seen in FIG. 2

of the drawings, which are joined by tie bolts 19. One

mesh with one another as seen in FIG. 2 of the drawings and one gear meshes with a pinion 36 which is alsolocated in recess32 and fixed on a shaft 38 rotatable in wall 20 and held against rotation by a pair of lock nuts 40 and 42 threaded onto the outer end of shaft 38, lock nut 40 being fixed to pinion 36 through an opening44 in cover plate 34.

Rollers 12 and 14 are each funnel-shaped with a neck 46 and an outwardly flaring circumferential shoulder 48 having an inset circumferential wear band 50. Rollers 12 and 14 are mounted on shafts 16 in parallel opposed relationship with sloping shoulders 48. facing one another. Each roller 12 and 14 is mounted on bearings 52 for free rotation on its shaft 16. Sealing rings 54 bear against the inner surface of each roller 12 and 14 to enclose bearings 52. Caps 56 cover bores 24 and 2 8 in wall 18 and cover 34 respectively.

Frame. 11 includes a pedestal 60 bevelled for lateral end of the frame and adapted to lie adjacent the nip of stands 62 as seen in FIG. 2. I I

. In the operation of the example embodiment a bar passesin the direction of arrow 82 thorugh mill stands 62 and into stripper guide 66 which directs the bar between rollers 12 and 14. As seen in FIG. 3 of the drawings, rollers 12 and 14 are spaced apart, in opposed relationship, to form a gap having the form of a parallelogram with one pair of opposed sloping sides formed by wear bands 50. As bar 80 meets rollers 12 and 14 it is twisted about its longitudinal axis in order to enter gap 90, bearing on wear bands 50 during contact of the bar with the rollers. Bar 80 travels on from twister guide 10 to an entry guide 92 which directs the bar into the nip of mill stand 64. As bar 80 travels between twister guide 10 and mill stand 64 the torque imparted to the bar by the twister guide causes it to continue twisting in the direction imparted to it by rollers 12 and 14, twisting a full 90 by the time the bar reaches the mill rolls. Consequently the degree: of twist imparted to bar 80 by twister guide 10 is dependent upon the distance between rollers 12 and 14 and mill stand 64 and since that distance is fixed, rollers 12 and 14 must be set and maintained accurately for a bar 80 of given cross-section. This is achieved, as bands 50 are worn down, by reducing the distance between the funnels 48 of rollers 12 and 14, i.e., by reducing the horizontal width of gap 90, while keeping the location of the cen tre line of bar 80. in a constant location. To move rollers 12 and 14 horizontally and in opposite directions for this purpose, pinion 36 is rotated through nut 40 which, as seen in FIG. 2, rotates spur gears 30 in opposite directions. Acting through splines 29, spur gears 30 roe tate shafts 16 which move axially in opposite directions by the engagement of threads 22 in bores 24 in wall 18 of frame 10. FIG. 3. shows rollers 12 and 14 positioned the example embodiment on a bar 80 of given crosssection is approximately between 20 and 35 (the maximum degree of twist being represented by phantom line 94).

I claim:

l. A twister guide for use between sets of mill stands comprising:

a frame;

a pair of substantially parallel guide rollers mounted on the frame, the guide rollers eachhaving anoutwardly sloping circumferential shoulder, the rollers being spaced apart and the shoulders being positioned in parallel, spacedrelationship to provide a gap, each guide roller being journally mounted on a shaft, the shafts being movable axially on the frame, one end of each shaft being threaded to engage a bore in the frame, the other end of each shaft being slidable axially in a bore in the frame and being splined slidably to engage a coaxialgear, the gears being meshed one with the other; and means to rotate at least one of the gears whereby the rollers are movable axially in unison and in opposite directions one to the other to vary the gap beis keyed on a pinion shaft rotatable on the frame, and tween the shoulders thereof. 2. A device as claimed in claim 1 in which the means to rotate at least one of the gears comprises a pinion.

3. A device as claimed in claim 2 in which the pinion 5 means fixed to the pinion shaft for engagement by rotating means. 

1. A twister guide for use between sets of mill stands comprising: a frame; a pair of substantially parallel guide rollers mounted on the frame, the guide rollers each having an outwardly sloping circumferential shoulder, the rollers being spaced apart and the shoulders being positioned in parallel, spaced relationship to provide a gap, each guide roller being journally mounted on a shaft, the shafts being movable axially on the frame, one end of each shaft being threaded to engage a bore in the frame, the other end of each shaft being slidable axially in a bore in the frame and being splined slidably to engage a coaxial gear, the gears being meshed one with the other; and means to rotate at least one of the gears whereby the rollers are movable axially in unison and in opposite directions one to the other to vary the gap between the shoulders thereof.
 2. A device as claimed in claim 1 in which the means to rotate at least one of the gears comprises a pinion.
 3. A device as claimed in claim 2 in which the pinion is keyed on a pinion shaft rotatable on the frame, and means fixed to the pinion shaft for engagement by rotating means. 